JPS59155018A - Manufacture of membrane - Google Patents

Abstract

PURPOSE:To obtain a membrane excellent in air permeability, by molding a thermoplastic resin composition containing a plasticizer into a sheet with a plurality of stepped sections, extracting the plasticizer so as to make the sheet have fine pores, and then stretching the resulting sheet that has the fine pores and the stepped sections so as to make the sheet flat. CONSTITUTION:For example, a polyethylene resin composition containing a plasticizer such as DOP, DOA, etc. is extruded from a mouth piece having bends in crosssection into a sheet with a plurality of stepped sections A-D, and then the plasticizer is extracted with a liquid of Flon or the like so that a sheet having stepped sections and fine pores 1 that pierce through the sheet can be obtained. Then the resulting sheet is stretched to be made flat so that the intended film that has vertically extending fine pores 1 and horizontally extending fine pores 2 can be obtained. Thus, if the present membrane is used as a ground material of a roof for a pen, sweating can be prevented, and light screening and heat screening that are required for a pen can be secured effectively.

Description

[Detailed Description of the Invention] A novel production method for a diaphragm film that, when used as a roof base material for a storage shed, can prevent the conventional drawback of forming a large amount of dew and dripping into the storage shed. It is about law.

Traditionally, breathable diaphragm films have been made with plasticizers such as D
The polyethylene/lipid composition containing OP is extruded into a film using a T-die, and then the plasticizer is mixed with a solvent.
Countless fine pores are formed by protruding, and as shown in the cross-sectional model diagram of a conventional diaphragm film in Fig. Although the film has vertical micropores 1, the conventional manufacturing method described above has the disadvantage that it is impossible to provide countless horizontal micropores that pass through the film in the cross-sectional direction.

The present invention provides a novel breathable diaphragm film that can eliminate the above-mentioned conventional drawbacks by providing a diaphragm film with numerous vertical micropores in the upper and lower surface directions and innumerable horizontal micropores in the cross-sectional direction. The purpose of the present invention is to provide a manufacturing method in which a thermoplastic resin composition containing a plasticizer is formed into a sheet having a plurality of steps, and then the plasticizer is extracted. A method for producing an air-permeable diaphragm film is provided, which comprises stretching the obtained stepped sheet-like material having numerous micropores into a flat plate.

Hereinafter, the present invention will be explained with reference to the drawings. Fig. 1 shows an example of a stepped 7-t-shaped article having countless micropores, which is an intermediate product of the present invention, and Fig. 2 shows an example of the intermediate product shown in Fig. 1. FIG. 1 is a cross-sectional model diagram of an example of the breathable diaphragm film of the obtained product of the present invention. Note that the term "model diagram" refers to a simple model of a structure in which innumerable vertical or horizontal micropores are actually intertwined in a vertical or horizontal straight line.

To carry out the production method of the present invention, for example, the plasticizer DOP
+ A polyethylene resin composition containing DOA, DO8, DBS, etc. is extruded using a cross-sectional bending die to obtain a stepped sheet having a plurality of stepped portions A, 'B, C, D, etc., and then, for example, a fluorocarbon liquid is extruded. By extracting the plasticizer, a multi-tiered sheet having numerous vertical fine holes 1 penetrating the upper and lower surfaces of a notebook, an example of which is shown in the cross-sectional model diagram of FIG. 1, is produced as an intermediate product.

Next, this intermediate product is stretched and made into a flat plate shape. As shown in the cross-sectional model diagram of FIG. Micropore 2
The breathable diaphragm film of the product of the present invention (hereinafter simply referred to as "diaphragm film") obtained in this manner can be obtained by To actually use it as a roofing material for buildings, etc.,
First, the left edge of the diaphragm film 3 of the product of the present invention and the left edge of the corrugated plate 4 are bonded L-L as shown in the schematic perspective view of FIG.
Then, an adhesive is applied to some or all of the peaks and valleys of the corrugated plate 4, and the film 3 is attached sequentially from the L direction to the R direction. The corrugated plate 4 shown in the schematic cross-sectional view of FIG. 5 after the diaphragm film 3 has been pasted is used with the diaphragm film 3 facing the main building side.

As detailed above, when the diaphragm film of the present invention is used, for example, as a base material for the roof of a storage shed, it can produce the following excellent industrially valuable effects that have not been seen before. It is something.

(1) The diaphragm film of the product of the present invention has vertical micropores that penetrate the upper and lower surfaces of the film and horizontal micropores that penetrate in the cross-sectional direction, so moisture in the storage building permeates and collects through each micropore by capillary action. However, due to the presence of the horizontal fine holes, the stains quickly move down the slope of the roof, thereby preventing the conventional drawback of condensation and dripping into the storage building.

(2) By combining the hollow parts with vertical and horizontal fine holes, it is possible to more effectively exhibit the light-shielding and heat-shielding effects necessary for livestock barns, etc.

(3) Therefore, it is not only hygienic but also has a positive effect on the definition of body storage.

[Brief explanation of drawings]

Fig. 1 shows an example of a stepped notebook-like product with fine pores, which is an unexploded intermediate product, and Fig. 2 shows an example of a sample film of the product of the present invention obtained from the intermediate product shown in Fig. Figure 3 shows the conventional granite film, each cross-sectional model diagram,
FIG. 4 and FIG. 5 are a tilted view and a schematic cross-sectional view illustrating one embodiment of using the diaphragm film of the present invention as a base material for a laminated roof. 1. Vertical micropores, 2. Horizontal micropores, 3. Diaphragm film, 4. Plating, A IB IC+D. Stepped portion. Patent applicant Mitsubishi Plastics Co., Ltd. agent Patent attorney Tsunebe Ogawa 11 Riki A O 2 (talented, 31 Tosuke 41)

Claims (1)

[Claims] A thermoplastic resin composition to which a plasticizer has been added is molded into a sheet having a plurality of steps, and then the plasticizer is extracted, and the obtained stepped sheet having numerous micropores is stretched. A method for producing a breathable diaphragm film characterized by forming it into a flat plate.